1. Field of the Invention
This invention lies in the field of X-ray machines. More particularly, it concerns industrial X-ray machines which are used on a continuous basis and require positive cooling means to protect the electrical apparatus and the X-ray tube inside the housing.
2. Description of the Prior Art
In the art of continuous duty industrial X-ray machines, one of the most important factors is the cooling system. All of the units which have substantially a hundred percent duty cycle incorporate some kind of remote external heat exchanger. Some use a Freon refrigeration system complete with cooling lines and hoses connected between the cooling unit and the X-ray machine. Others use an oil or water cooling system again complete with inner connecting hoses between the X-ray machine and a small automotive type radiator with fan, etc. Still others simply connect the unit by a water hose to a water tap and use city water pressure to circulate cooling water through the X-ray unit and then down the drain.
These units operate satisfactorily but are heavy, bulky, and are not truly portable, although usually advertised as such. This is because of the hoses and accessories required for cooling. There is no problem with these units when the X-ray machine is installed permanently in a shooting vault and the parts to be radiographed are moved to and from the X-ray unit. The problems arise when the X-ray machine must be used on a cross-country pipeline, moved in and out of pressure vessels in a tank shop, or from one location to another in a foundry.